Raunch-com, we need to talk. We’ve been spending a lot of time together (11 years, by my count), and this relationship just isn’t working out for me anymore. Every time you start to tell me a new story, I get all excited, thinking, “This ought to be good,” only to discover that this story just cobbles together elements from the stories you told me a couple of years ago. Do you even recognize that you’ve told this joke before? There are times when I feel like Julianne Moore’s husband in “Still Alice,” if “Still Alice” was a pitch-black comedy. Funny, yet so not funny.

And yet, there are times when you can still bring the goods, though with your most recent story, “Mike and Dave Need Wedding Dates,” your ass was saved by some expert casting. Aubrey Plaza? Genius move. it was economical as well, at 98 minutes. Way to get in and out before wearing out your welcome.

Mike (Adam Devine) and Dave (Zac Efron) are dipshit party boy liquor salesmen who have a history of ruining family events with their brotastic shenanigans. The next family event is the wedding of their little sister Jeanie (Sugar Lyn Beard), so the parents give them an ultimatum: they must bring dates, and nice ones at that, so they will be encouraged to behave themselves. The boys are struggling with the concept, so in their infinite wisdom they decide to put out an ad, which quickly goes viral and catches the eye of party girl Tatiana (Plaza), who sees an all-expenses-paid trip to Hawaii as the perfect way to get her left-at-the-altar bestie Alice (Anna Kendrick) out of her tailspin. Alice and Tatiana’s ruse is to lead the boys into thinking that they don’t know who they are and are just meeting them by chance. It works, but not for as long as they had hoped.

It may be based on a true story, but “Mike and Dave” is a veritable Frankenraunch of a script, stealing bits from “Couples Retreat” (the massage), “Bridesmaids” (the horny wedding guest), and “Just Go with It” (the web of lies, and a destination wedding in Hawaii), while making direct references to “Wedding Crashers” and “Jurassic Park.” Curiously, four of those five properties are owned by Universal, yet this movie was made by 20th Century Fox. Huh.

Whatever inconsistencies there are with the character arcs (and there are), it’s a testament to the casting that so many of them are quickly forgiven. Plaza owns the first half of the film as she teases Devine until he practically explodes, and then Kendrick turns up her doe-eyed charm to bring the movie home. The biggest surprise here, though, is Efron. He more than holds his own opposite his formidable female leads while inadvertently wiping the floor with Devine, who doesn’t seem at all prepared for the showcases that happen all around him. Never mind Efron, Kendrick and Plaza; Devine gets owned by Stephen Root (who plays his father), little sister Beard in a star turn, Sam Richardson as Jeanie’s husband-to-be, and Alice Wetterlund as Cousin Terry, a.k.a. this movie’s Melissa McCarthy, channeling Kate McKinnon.

While those character inconsistencies may be forgiven, though, they’re not forgotten. Kendrick and Plaza conveniently turn their hot mess factor on and off like it’s a light switch, and there is rarely a moment where the audience isn’t aware of that, especially when Kendrick turns the switch back on at the least opportune time. There are also some egregious plot issues, like the DJ who doesn’t have the wits to kill the power when his audience is overhearing a conversation that isn’t meant for them. “Nope, everyone needs to hear this, or the plot can’t go forward!” Jesus.

There is nothing in “Mike and Dave Need Wedding Dates” that hasn’t been done before. That it’s still occasionally amusing is to its great credit. With the talent involved, though, it’s not unreasonable to expect something better. It’s not me, raunch-com: it’s you.